Hmm, interesting...but why stay there when she could be with him, her own grandad...? Why can't Gallifrey be time travelled on? Now of course not becuase it's destoryed, but do you mean when it wasn't or now? Is the actual planet destroyed or just his people gone? I'm putting them together to create something else which might not be true.
Don't understand these.
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Credit to Kuchiki.
Susan had fallen in love with someone! The old fashioned reason. Several Doctor Who companions leave on that basis, and always to men that they only just met, which is a bit of a running Doctor Who joke.
Why can't Gallifrey be time travelled on? Your guess is as good as mine. Time Lords are kind of 'part' of Time itself in many ways, so the rules are different for them. But whatever the reason, although it has never been explicity stated it seems very likely that Gallifrey simply cannot be time travelled on.
As for the things you don't understand...
Point one. The Doctor shows the end of the Earth, and when that upssets her, he takes her back to before it was destroyed.
But then he says how his world has gone and he can never go back- the implication is that he cannot do what he just did for Rose, i.e. go back to before it was destroyed.
Point two- the idea of a stable timeline between Time Lords.
Ok- excepting special Anniversay shows where the Doctor meets himself, which normally means Time Lord rules are being broken, the point is that if you are always time travelling all over the Galaxy, you would think you would meet other people doing the same thing on a random basis.
Take the Doctor's nemesis, the Master, who has the same life as the Doctor except he tries to conquer rather than help. You might think that the third time the Doctor bumps into the Master, it might be the 9th time the Master has bumped into the Doctor, because they are time travellers and don;t have to meet up in order!
But no. Every time the Doctor and the Master meet, it hass always been the same amount of time for both of them since they last met.
And this seems true for every single interaction between the Doctor and his race and his planet. He never experiences them out of order. he has never been to Gallifrey before the last time he was there, or met another Time Lord before the last time he met him, from that Time Lord's point of view.
It is like they all live in their own continuous time stream that is constant even though they are all time travellers. And now, with his homeworld destroyed, he cannot even go back in time to see it how it was.
Hence the theory about time travel being different for Gallifrey.
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"We've got maybe seconds before Darth Rosenberg grinds everybody into Jawa burgers and not one of you buds has the midi-chlorians to stop her!"
I just watched the final story again and all I saw going into the void was the Daleks with the exception of the Black Dalek. I did not see a single Cyberman go into the void, strange. I shall put this down to a special effects error.
__________________ "Too bad she won't live, then again who dose."
I just remembered something about the Tardis after the Key to Time story's didn't the Doctor insert a randomiser which resulted in no control of the Tardis, so the Doctor could shake off the Black Guardian. Yes I know he turns up again. I must assume the Doctor got rid of the randomiser latter on.
__________________ "Too bad she won't live, then again who dose."
Besides, it was crap. It took him to Earth and then Skaro, the first and third most visited places in Doctor Who (the second being Gallifrey). Hardly random.
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"We've got maybe seconds before Darth Rosenberg grinds everybody into Jawa burgers and not one of you buds has the midi-chlorians to stop her!"
Well. You did see the Cybermen rise into the air and then dissapear. Also, according to the episode commentary Russell whats his face states that they get pulled through the smaller faultlines whereas the Daleks get pulled through the main breach.
Gender: Female Location: Dreaming about David Tennant...
I listened to the commentary as well, so maybe if no-one else feels like explaining properly:
The Doctor even explained it to us. (Well, to Tracy-Ann Cyberman [I'm not kidding, that's what they called her!].Well, he explained it to Yvonne). As he said, they came through the fault-lines (don't you remember him breaking the glass in her office?), NOT through the actual hole in the universe that the void ship made. All of the DALEKS came through the actual hole, but the Cybermen just came through the fault-lines. D'you remember how they appeared? As ghosts? Those were where the fault-lines were. So, they just disappeared through there again. Only this time, they couldn't even get back to their own universe, because the breach was being closed.
Do you get that? Sorry, I'm not too fantastic with explaining. Everyone should get the commentary! It's really good, and really informative. And it's funny.